hydrogen [4-[4-(diethylamino)-alpha-(2,7-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]diethylammonium

N-[4-[[4-(Diethylamino)phenyl](2-sulfo-7-sulfonato-1-naphthalenyl)methylene]-2,5-cyclohexadien-1-ylidene]-N-ethylethanaminium